I am in the jungle, filming in the heart of Amazonia. Not much room in my backpack for mobile phones, game consoles or laptops but just enough for a pair of compact cameras with which to attempt to capture the nuanced colourations of the red howler monkey, the pink river dolphin, the scarlet mosquito bite and the purple leech gash. I have a Sony Cybershot DSC-T200 and a Casio EX-S880, two cameras crammed to point of madness with the latest innovations in digital photography.

Compact cameras have arrived at That Stage. They work very well. Resolution is high. We have swiftly leapt from two to three to five to eight to 12 megapixels. Memory cards are cheap and contain far more capacity than could ever be sanely used. I slipped an 8GB stick into the Cybershot without thinking. No matter how many photos I take, they will rattle around in that cavern of memory like a pea in a cathedral. So we can take more pictures than ever before. We can lodge them on more photosharing sites than are necessary to store the sum of human knowledge.

But there is a problem for Canon, Nikon, Pentax, Fuji, Panasonic, Leica, Olympia, Casio, Sony, Kodak and the rest: why should anyone keep buying new kit? Just about everybody who needs a camera has one. What is wrong with that Ixus I bought three years ago? That old Pentax Optio will see me through to my old age, won't it? No! No, you crazed enemy of freedom, you wild-eyed anti-capitalist, you deranged luddite. Haven't you heard of Face Detection Technology? Smile Capture? Best Shot Automatic YouTube Uploading?

This is what I mean by That Stage. The manufacturers are now running round in a frenzy inventing more and more zany capabilities and over-specific presets (Candlelight, Fireworks, Baby, Street Scene and so on) in an attempt to persuade us that we must have a new model.

The 8.1 megapixel Casio Exilim is a well-designed camera, slim as a reed and, in the version I was sent, a perky red colour. The stickers that deface the otherwise attractive object trumpet "YouTube Capture Mode" and "Face Detection". The former is a Windows only capability. You install a YouTube uploader on to your PC, attach the camera when it has shot some footage in the "YouTube Best Shot" mode and the software does the rest. If you have never uploaded a movie to YouTube before, please do not think you need a special uploader. Uploading is the simplest thing in the world. This can be proved by observing that the kind of people who do it most are often barely sentient. So a YouTube uploader you do not need.

Face Detection? This is the new sine qua non. Select it and the camera automatically senses one or more human faces and bounds them in a rectangle. When you shoot, the areas in the rectangles are given exposure and focus priority. Fine if they're all more or less on the same focal plane, in which case all you would have to do is point at one face, half depress the shooting button as usual and then reframe with your finger still down. That has been a feature of autofocus cameras for at least 15 years. The Sony Cybershot (also 8.1 MP) offers face recognition and Smile Detection. When a detected face smiles, the shutter automatically fires, for up to six shots. The Casio ripostes not with Smile Detection, but with Family First. You photograph your family, the camera stores their face, recognises it the next time you shoot and prioritises them in a group of disparate, non-family faces. This "technology" was developed in Japan, so whether it thinks western faces are all the same I haven't had the patience to discover. These extras are batty and pointless.

The Sony has a touchscreen display, which works well. It also outputs via an HD cable to your new flat screen TV. The Casio uses a bothersome charging cradle. They are good cameras, but stuffed with insane, desperate, and unnecessary nonsense which is in danger of compromising that simplicity of use which is what attracts people to compact digitals in the first place. If you need a new camera, either will suit you. I prefer the Casio, it's neater, prettier and doesn't use expensive memory sticks, but it is virtually a tie.